It has become more usual to provide items of goods offered for sale in self-service stores with a bar code which is read-off at the cash desk of the store, thereby to record automatically the price of said item, among other things. One alternative in this regard is the use of a so-called hand-scanner, i.e. a scanner which is held by the cashier and passed over the bar code on the goods item concerned, said scanner reading the bard code optically and delivering to a computer or microprocessor an electric signal which corresponds to the information contained in the bar code.
It has also become progressively more usual in recent times to provide price-tagged goods with a magnetic alarm strip in conjunction with the price tags, said strips being intended to coact with transmitter coils and receiver coils positioned in the vicinity of the cash desk or an exit, so that if a customer fails to present an item of goods for payment, an alarm signals is triggered when the goods item is passed between the coils.
In order to prevent the triggering of an alarm by goods which have been paid for, the alarm strip on the price tag is deactivated by exposing the strip to a powerful permanent magnetic field. At present, this is effected by holding the price tag close to a fixedly mounted permanent magnet. This method necessitates the cashier first to pass the goods past the scanner with the bar code on the goods facing towards the scanner and then to move the price tag on the goods against the permanent magnet. Thus, the cashier is required to perform two different procedural steps, namely one step involving recording the item of goods by reading the bar code and another step involving deactivation of the alarm strip.